Europa changed how we saw the solar system | The Verge

"On Monday, NASA is set to hold a press conference about some “surprising activity” on Jupiter’s icy moon of Europa. There’s no indication as to what that activity might be, other than it involves the Hubble Space Telescope, but it’s garnering more than one 2010 reference around the internet. Europa has always been a fascinating world that has challenged our view of the nature of the solar system.

First Glimpse



Europa was discovered by accident. Galileo Galilei turned his telescope to observe Jupiter on January 7th, 1610, when he made a startling discovery: the planet was accompanied by four small objects, and over the next several nights, he determined that these objects orbited the planet. He wasn’t alone in this observation: a German astronomer named Simon Marius spotted the same points of light the night on the night of the 6th and gave each object their present names: Io, Europa, Ganymede, and Callisto.



The discovery of these moons was a major advance in the understanding of how the solar system worked. Galileo realized that Jupiter was the center of an orbital system, which contradicted the teachings of the day. David A. Weintraub wrote about Galilelo in his book Is Pluto A Planet: A Historical Journey through the Solar System, “The motion of the Medicean stars around Jupiter demonstrat[ed] that Aristotle was wrong about the Earth being the only center of motion in the universe.”



The discovery placed Galileo in opposition to the Catholic Church, which deemed his research and findings heresy. He was admonished in 1616, and later interrogated and forced to recant. In 1634, he was placed under house arrest for the remainder of his life."



Europa changed how we saw the solar system | The Verge